Coloring of organic materials with asymmetric thioindigoid compounds

ABSTRACT

Method of coloring an organic material with an asymmetric thioindigoid compound having the formula:

BACKGROUND OF THE INVENTION

This invention relates to a method for coloring organic materials,especially textiles, with asymmetric thioindigoid compounds.

The prior art has made little use of thioindigo derivatives as dyestuffsfor synthetic organic materials, especially for polyester fibers,although many thioindigo derivatives have been used for dyeing naturalfibers (for example, cotton). Recently, brilliant nuance has beendesired in colored articles, especially in weaving apparel, whilepolyester materials colored with ordinary dyestuffs for polyester show aduller hue than the other colored synthetic organic materials (forexample, polyacrylonitrile fabrics). Thus, brilliant dyestuffs forpolyester materials have been sought.

This situation is also testified by the invention of "cationicdye-dyeable polyester" that shows more brilliant hue by dyeing withcationic dyes than the hue of ordinary polyester materials dyed withordinary dyes for polyester. On the other hand, the thioindigoidcompounds show brilliant coloring effects but little dyeability forpolyester materials, and therefore thioindigoid dyes for polyesters havescarcely been known except that unsubstituted thioindigo is applied onlyin limited uses.

The present inventors have previously discovered that certain asymmetricthioindigoid compounds can be effectively used as dyes for the coloringof organic materials, especially for polyester fibers (West Germany, OLSNo. 2,401,981). The asymmetric thioindigoid compounds employed in theOLS No. 2,401,981 are good for dyeing the organic materials in a widecolor range of red to violet, but their dyeing properties are notnecessarily satisfactory in the color range of reddish orange to red. Itis desired therefore to find new asymmetric thioindigoid compoundshaving even better dyeing properties in a color range of reddish orangeto red.

As a result of intensive colorant tests an organic materials coloredwith the thioindigoid compounds, it has now been discovered that thecompounds of formula (I) below color synthetic organic high molecularweight compounds, especially polyester materials, in a reddish orange tored color of brilliant nuance with characteristic fluorescence. Besides,recently α-aminoanthraquinone, the most important intermediate forreddish diperse anthraquinone dyes, has caused difficult problems onenvironmental pollution because of using a mercury catalyst formanufacturing it. The new thioindigoid compounds used in this inventioncan be obtained without using mercury and color in more brilliant nuancethan the anthraquinone derivatives.

SUMMARY OF THE INVENTION

This invention relates to a method of coloring an organic material withan asymmetric thioindigoid compound having the formula: ##SPC2##

wherein

R is a hydrogen atom or a lower alkyl group preferably having 1 to 4carbon atoms;

R' is a member selected from the group consisting of

1. a hydrogen atom,

2. halogen atoms,

3. lower alkyl groups preferably having 1 to 4 carbon atoms,

4. lower alkoxy groups preferably having 1 to 4 carbon atoms,

5. a sulfonamide group the amide group of which can be optionallysubstituted with a member selected from the group consisting of

i. a lower alkyl group preferably having 1 to 4 carbon atoms which alkylgroup can be optionally substituted with

a. a hydroxyl group,

b. a lower alkoxy group preferably having 1 to 4 carbon atoms or

c. a cyano group,

ii. a cyclohexyl group,

iii. aralkyl groups and

iv. a phenyl group which can be substituted in its optional positionwith

a. a lower alkyl group preferably having 1 to 4 carbon atoms,

b. a chlorine atom or

c. a lower alkoxy group preferably having 1 to 4 carbon atoms, and

6. aryl sulfonate groups the aryl group of which can be substituted inits optional positions with

i. a halogen atom,

ii. a lower alkyl group preferably having 1 to 4 carbon atoms or

iii. a lower alkoxy group preferably having 1 to 4 carbon atoms;

R" is a hydrogen atom or methyl group; and

X is an oxygen atom or sulfur atom.

The organic materials which can be colored in accordance with thepresent invention include any synthetic or semisynthetic high molecularweight compound which can be formed into fiber, extrudate, casting ormolded article. The organic material may be synthetic or semisyntheticresins such as amino-formaldehyde resins (for example, urea-formaldehyderesin), polymers and copolymers of methacrylic acid esters, polymers andcopolymers of vinyl chloride, polymers and copolymers of vinylidenechloride, polymers and copolymers of olefins (for example, polyethyleneand polypropylene), styrene polymers and copolymers, polyamide resins,polyacrylic resins, polyacetal resins, cellulose esters (for example,cellulose triacetate), and especially polyester resins.

DETAILED DESCRIPTION OF THE INVENTION

Thioindigoid compounds have previously been well known as vat dyes andapplied to the dyeing of cellulose fibers, but for dyeing of man-madefibers, especially, polyester fibers, they have little dyeability.Therefore, to treat polyester fibrous articles with the hitherto knownthioindigoid compounds by conventional exhausting methods in aqueousmedia has shown little effect and has been practically useless.

The asymmetric thioindigoid compounds of formula (I) have not been knownyet. We, as a result of an intensive colorant test on organic materialswith the thioindigoid compounds, discovered that the compounds offormula (I) color synthetic organic high molecular weight compounds,especially polyester materials, in brilliant nuance with characteristicfluorescence, and thus completed the invention.

These discoveries are not anticipated from the facts known heretofore.The compounds of formula (I) having a good affinity for polyestermaterials, can be applied by the same procedures as those employed withordinary disperse dyestuffs for polyester materials, and can color thearticles in brilliant nuance ranging from reddish orange to red shadewith fluorescence with various superior fastness characteristics.

Therefore, the compounds of formula (I) are suitable for use in printingpolyester fabrics.

The asymmetric thioindigoid compounds of the invention are easilysynthesized by known methods as follows: ##SPC3##

or; ##SPC4##

wherein Z is a substituted or unsubstituted amino group or aryloxygroup.

The thionaphthenone intermediates can be obtained, for example,according to the procedure: ##SPC5##

wherein R, R' and X are the same as those defined for formula (I).

Thus, for example, from 6-phenoxythionaphthenone-3-and2-(4'-dimethylaminophenylimino)thionaphthenone-3, 6-phenoxythioindigo(m.p. 240° - 242°C) is obtained. Similarly, 6-thiophenoxythioindigo(m.p. 225° - 227°C), 6-(p-cresoxy)thioindigo (m.p. 236.5° - 238°C) and6-(p-chlorophenoxy)thioindigo (m.p. 255° - 256°C) are synthesized. From6-phenoxythioindigo are obtained6-(p-dimethylsulfamoylphenoxy)thioindigo (m.p. 278° - 280°C) and6-(p-phenoxysulfophenoxy)thioindigo (m.p. 204° - 205°C) through thepreceding scheme. Therefore, we do not think it necessary to describespecific synthesizing methods for the compounds of formula (I) in thisapplication.

The compounds which provide the group Z are, for example, amines such asammonia, methylamine, ethylamine, n-butylamine, cyclohexylamine,benzylamine, phenethylamine, dimethylamine, dibutylamine,dicyclohexylamine, ethanolamine, γ-methoxypropylamine,γ-butoxypropylamine, cyanoethylamine, aniline, toluidine, chloroaniline,anisidine, benzidine, dichlorobenzidine, tolidine, methylenedianiline ordichloromethylenedianiline; or phenols such as phenol, cresol, xylenol,chlorophenol, ethylphenol, butylphenol, guaiacol, p-methoxyphenol,guaetol, α-naphthol or β-naphthol.

In Table 1, typical examples of the compounds used for this inventionare shown although the present invention is not limited thereto. Theshade of polyester fabric dyed therewith using a dyeing procedure suchas that described in Example 1 or 2 is specified. ##SPC6##

Organic materials can be easily colored with the compounds of formula(I) by any ordinarily practiced method. For example, a fibrous material,such as yarns and fabrics, can be colored by fixing, at 50° to 140°C, inaqueous medium by the conventional exhausting method, at 100° to 150°Cby the conventional printing with saturated steam (applicable 150° to180°C super-heated steam), or at a suitable temperature (100° to 200°C)consistent with the type of fiber using dry heat by the conventionalthermosol method. The application of the thermosol method is especiallypreferable to for dyeing polyester fabrics at a treating temperature of180° to 220°C.

When the organic material to be colored is a film, coating, casting or amolded or extruded article, it can be colored by admixing the compoundof formula (I) with a resin or polymer during the preparation of such aresin or polymer, or before it is used to form such an article, orduring the formation of such a resin into the article. Also, a resinbased pigment having reddish orange to red shade with fluorescence canbe obtained by mixing the compounds of formula (I) into the resin orpolymer or other properly selected organic materials in molten form.

Table 2 shows the differences between the two reddish orange dyeings ofpolyester which were obtained according to the present invention and theaforesaid OLS No. 2,401,981 respectively.

                                      Table 2                                     __________________________________________________________________________                                                          Sublimation             Invention                                                                            Compound                         Hue    Build up                                                                             fastness*               __________________________________________________________________________    OLS                                      Reddish-                                                                            Poor   3(0.6% of owf)          2,401,981                                orange                               Present                                  Ditto Excellent                                                                            4(0.6% owf)             Invention                                                                     __________________________________________________________________________     *JIS L 0879-1968:B                                                       

According to the present invention, it is possible to obtain reddishorange to red dyeings of organic materials in brilliant nuance withcharacteristic fluorescence and excellent fastness, which cannot beachieved by the method of the OLS No. 2,401,981.

The following examples are presented in which all parts are on a weightbasis and the compound numbers refer to the compounds described in Table1.

Example 1

One part of compound No. 1 (6-phenoxythioindigo) was ground togetherwith 0.5 part of a sodium alkylbenzenesulfonate oralkylarylpolyoxyethylene ether as a surface active agent and 2 parts ofwater for a sufficient time to provide a finely granulated powder whichwas diluted with water to provide 10 parts of a finely granulatedaqueous dispersion, 0.2 part of this dispersion was added to an aqueousbath containing 1 part of a higher alcohol sulfate type surface activeagent to provide 500 parts of a treating bath. 10 parts of a polyestercloth was immersed in this treating bath maintained at 130°C. for 40minutes and was water-washed and dried. The dyed cloth showed a clearreddish orange color having an orange fluorescence and its lightfastness and sublimation fastness were 5th grade (JIS L 0842-1971) and4th grade (JIS L 0879-1968:B) respectively. Similarly, a dyed clothshowing a similar color, having similar fluorescence and fastnesses wasobtained by using compounds No. 2, 3, 4, 7, 8 and 9 respectively insteadof compound No. 1 mentioned above. A triacetate cloth, instead of thepolyester cloth, was treated in the same manner as above, and resultssimilar to those on the polyester cloth were obtained.

Example 2

One part of a finely granulated sample of compound No. 2(6-chlorophenoxythioindigo obtained in the same manner as described inExample 1 was dispersed in 20 parts of water containing 0.04 part of apolyoxyethylene alkyl ether as a surface active agent.

A polyester cloth was dipped in this aqueous dispersion and impregnatedwith the dispersion at a pick-up of 40 - 50%. This treated cloth wasdried, heat treated at 180°C. for 1 minute, washed with a dilute surfaceactive agent solution, washed with water and dried to provide a dyedcloth of clear reddish orange color having an orange fluorescence, lightfastness of 5th grade (JIS L 0842-1971) and sublimation fastness of 4thgrade (JIS L 0879-1968:B).

Example 3

An aqueous dispersion of compound No. 1 was provided in the same way asdescribed in Example 1. Then, a color paste of the following recipe wasprinted in a pattern on a polyester cloth.

    ______________________________________                                        Dispersion of dyes in Example 1                                                                         3      parts                                        Water                     36     "                                            Stock thickening          60     "                                            Anti reductant            1      "                                            [Stock thickening was prepared as follows:                                    Neugen ET                 1      part                                         (surface active agent made by                                                 Daiichi-Kogyo-Seiyaku K.K.)                                                   Water                     14     parts                                        Turpentine oil            35     "                                            5% Sodium alginate water solution                                                                       50     "                                            were thoroughly mixed in half emulsion.]                                      ______________________________________                                    

The printed cloth was steam-heated at 150° to 180°C. for 3 to 5 minutesin a high temperature steamer, washed with a dilute solution of asurface active agent, then washed with water and dried. The pattern ofthe cloth obtained showed a clear reddish orange color, and its dyeingfastness characteristics were similar to those of the dyeings obtainedin Example 1. Similarly, with the compound No. 12 the pattern havingclear reddish orange color and sublimation fastness of 5th grade (JIS L0879-1968:B) was obtained.

Example 4

A uniform mixture consisting of 0.1 part of compound No. 4[6-(4'-methylphenoxy)thioindigo], 50 parts of polyvinylchloride and 50parts of dioctylphthalate was kneaded at 150°C, for 10 minutes and wasthen pressed for 5 minutes between metal plates heated to 160°C. to makea sheet with a thickness of about 0.5 mm.

The sheet thus obtained showed a clear reddish orange color emitting anorange fluorescence.

Example 5

0.01 part of compound No. 5 (6-thiophenoxythioindigo) was added to 10parts of polystyrene, kneaded at 180°C. for several minutes and was thenpressed to a plate 5 mm thick.

The polystyrene plate thus obtained showed a clear pink color withfluorescence.

Example 6

20 parts of an unmodified melamine-formaldehyde resin was mixed into 50parts of a sulfonamide resin melted at 120°C.

The resulting mixture was heated to 170° - 180°C. and 1 part of compoundNo. 7 (6-phenoxy-6'-methylthioindigo) was mixed with the mixture.

The mixture was completely dissolved, then cooled, solidified and thencrushed to obtain a reddish-orange fluorescence pigment emitting anorange fluorescence.

What is claimed is:
 1. A method for dyeing synthetic or semi-syntheticpolymeric fibres with an asymmetric thioindigoid compound having theformula: ##SPC7##wherein R is a hydrogen atom or lower alkyl group; R'is a member selected from the group consisting of1. a hydrogen atom, 2.halogen atoms,
 3. lower alkyl groups,
 4. lower alkoxy groups,
 5. asulfonamide group the amide group of which may be substituted with amember selected from the group consisting ofi. lower alkyl groups whichmay be substituted witha. a hydroxyl group, b. lower alkoxy group or c.cyano group, ii. a cyclohexyl group, iii. aralkyl groups and iv. aphenyl group which may be substituted witha. a lower alkyl group, b.chlorine atom or c. lower alkoxy group, and
 6. aryl sulfonate groups thearyl group of which may be substituted withi. a halogen atom, ii. loweralkyl group or iii. lower alkoxy group; R" is a hydrogen atom or methylgroup; and X is an oxygen atom or sulfur atom.
 2. The method as claimedin claim 1, wherein R and R" are a hydrogen atoms; and R' is a memberselected from the group consisting of a hydrogen atom, chlorine atom,lower alkyl groups and lower alkoxy groups.
 3. The method as claimed inclaim 1, wherein R and R" are a hydrogen atom; and R' is a memberselected from the group consisting of1. a sulfonamide group the amidegroup which may be substituted with alkyl groups which may besubstituted with a lower alkoxy group and
 2. aryl sulfonate groups thearyl group of which may be substituted withi. a halogen atom, ii. loweralkyl group or iii. lower alkoxy group.
 4. The method as claimed inclaim 2, wherein the asymmetric thioindigoid compound has the formula:##SPC8##
 5. The method as claimed in claim 2, wherein the asymmetricthioindigoid compound has the formula: ##SPC9##
 6. The method as claimedin claim 2, wherein the asymmetric thioindigoid compound has theformula: ##SPC10##
 7. The method as claimed in claim 3, wherein theasymmetric thioindigoid compound has the formula: ##SPC11##
 8. Themethod as claimed in claim 3, wherein the asymmetric thioindigoidcompound has the formula: ##SPC12##